Synonyms

Definition

Transient statistical/stochastic fluctuations in equilibrium thermodynamic properties that occur in any system in thermal contact with its surroundings.

Introduction

Due to the incessant thermal motion of atoms and molecules, all objects that are in thermal contact with surroundings will experience statistical fluctuations in internal energy, volume, and other extensive thermodynamic properties, even at thermodynamic equilibrium. These fluctuations are usually imperceptible in everyday macroscopic objects, except in special circumstances*, but take on much greater significance for much smaller (mesoscopic, microscopic) objects. This is particularly important for biological macromolecules where fundamental thermodynamics dictates dynamic characteristics.

[*The effects of thermodynamic fluctuations on a larger scale are observable as the chaotic motion of small objects seen in Brownian...